/*
 * jPOS Project [http://jpos.org]
 * Copyright (C) 2000-2015 Alejandro P. Revilla
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.jpos.iso;

/**
 * ISOFieldPackager CHARACTERS (ASCII and BINARY)
 * deal fields terminated by special token
 *
 * @author Zhiyu Tang
 * @version $Id$
 * @see ISOComponent
 */
public class IF_TCHAR extends IF_TBASE {
	public IF_TCHAR() {
		super();
	}

	/**
	 * @param len         - field len
	 * @param description symbolic descrption
	 */
	public IF_TCHAR(int len, String description) {
		super(len, description);
	}

	/**
	 * @param len         - field len
	 * @param description symbolic descrption
	 * @param token       token descrption
	 */
	public IF_TCHAR(int len, String description, String token) {
		super(len, description, token);
	}

	/**
	 * @param c - a component
	 * @return packed component
	 * @throws ISOException
	 */
	@Override
	public byte[] pack(ISOComponent c) throws ISOException {
		String s = c.getValue() + getToken();
		return s.getBytes();
	}

	/**
	 * @param c      - the Component to unpack
	 * @param b      - binary image
	 * @param offset - starting offset within the binary image
	 * @return consumed bytes
	 * @throws ISOException
	 */
	@Override
	public int unpack(ISOComponent c, byte[] b, int offset)
			throws ISOException {
		String s = new String(b, ISOUtil.CHARSET);
		int newoffset = s.indexOf(getToken(), offset);
		c.setValue(s.substring(offset, newoffset));
		int len = newoffset - offset;
		setLength(len);
		return len + getToken().length();
	}

	@Override
	public int getMaxPackedLength() {
		return getLength() + getToken().length();
	}
}
